A problem which may be addressed by the present invention is described below, in an example for injection valves or injectors for internal combustion engines.
Modern engines attain a high energy yield per fuel quantity unit used, and an exhaust that is low in pollutants, based among other things on precise injection of the fuel into the combustion chambers. In this connection, both the great accuracy of the time of injection and of the injection quantity is ensured by an injection control. The injection control controls a plurality of injectors.
Because of manufacturing conditions, the injectors have tolerances with respect to the injection quantity as a function of parameters such as the control time, fuel chamber pressure, etc. In order to ensure precise injection in spite of these tolerances, each injector is measured individually. The characteristics curves of the respective injectors ascertained in this connection are, for example, printed onto them in bar code or are stored in an EEPROM of the injector, as is described in German Patent Application No. DE 102 44 094 A1.
Before or during the mounting of the injectors, the characteristics curves are read in or out and transmitted to the injector control. Besides the EEPROM on the injectors, the injectors described in German Patent No. DE 102 44 094 have an additional data connection via which the characteristics curves are able to be read out by the injection control. The additional connections and data lines require an increased wiring expenditure and represent additional potential weak points, for instance, on account of loose connections.